Process for treating hydrocarbon oils



May 10, 1927. c. P. DUBBS PROCESS FOR TREATING HYDROCARBON OILS Filed Dec. 17.. 1921 5 Sheets-Sheet 1 May 10, 1927.

C- P. DUBBS PROCESS FOR TREATING HYDROCARBON OILS Filed Dec.l'7, 1921 5 She et's-Sheet 2.

May 10, 1927. 1,628,127

I c. P. DUB BS I PROCESS FOR TREATING HYDRQCARBQN O ILS Filed Do'. 17, 1921 s Sheets-sheaf W rl WQW 4? parts broken away.

Patented May 10, 1927.

UNITED STATES PATENT OFFICE.

CARBON I. DUBBS, OF WILMETTE; ILLINOIS, ASSIGNOR TO UNIVERSAL OIL PRODUCTS COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF SOUTH DAKOTA;

PROCESS FOR TREATING HYDROCABBON OILS.

Application filed December 17, 1921. Serial No. 523,113.

This application is a continuation in part of my co-pending application Serial No. 204,527, filed Nov. 30, 1917.

Among the salient objects of the invention are to provide an improved process in which the heated hydrocarbons are circulated through a coil still and then passed to a condenser, and during such treatment subjected to the pressure of the generated vapors;to provide a process in which the temperature and pressure are readily and accurately controlled; to provide a process wherein the circulation of the hydrocarbons being treated is readily and accurately controlled; to provide a process which can be operated continuously; to provide a process which avoids the danger of the tubes in which the hydrocarbon is heating from being burned out by preventing the precipitation of carbon on said tubes, this being accomplished b means of the rapid circulation of the oil tlirough said tubes; to provide a process in which such products that are only partly converted to the desired low boiling point are returned and further treated in the distilling tubes; to provide a process where, by means of air-cooled condenser, the grade of distillate allowed to pass from the system is controlled, and such distillate not up to a desired grade is condensed and automatically returned to distilling coils and redistilled; to provide a process in which the heating tubes and the distilling tubes are maintained in a furnace held within well defined temperature ranges, and the oil caused to circulate through said heating tubes at such velocity as to prevent any great amount of carbon depositing on said tubes; and, in general, to provide an improved process 0 the character referred to.

In the drawings:

Fig. 1 and Fig. l together show a side elevation partly in section and with other Fig Pie 9. side view of the liquid level regulator and diaphragm valve, shown in fra mentary section.

ig. 2 and Fig. 2 are a plan view of the construction shown in Figs. 1 and 1.

I Fig. 3 is an end elevation of the condensmg members.

Fig. 4 is a view, partly in elevation and partly in section, of the heating coils.

Referring to the drawings, A are the furnaces in which the heating tubes and distilling tubes are positioned. A are the tunnels through which the fire for heating the furnaces passes. A are the furnace flues. A is the flue stack.

B constitute parallel substantially level heating tubes, and B constitute substantially level distilling tubes. B B, B and B are return Ts on the heating tubes. B, B and B are return Ts on the distilling tubes. B and B are fittings around the tubes for anchoring the particular tubes shown. All the tubes extend through the furnace walls and are free to expand independently thereof, with the exception of where the two tubes are anchored. B and B are braces for supporting the tubes-B and B C is a feed line from any source of supply to pump C and in this line is throttle valve C (1* is the charging line from the pump to the heating tubes B, and in this line is the throttle valve C. C and C are motors for operating the pumps C and C. C is a pump which is supplied through line (1 branching from the suction line C. C" is the discharge line connectin this pump with charging line C, and br nching off of discharge line (J is a branch line C which connects with suction line C and having positioned on it a pressure relief valve or by-pass valve C. U is a meter of an standard make suitable for the work in han go 0 is a standard make check-valve. C" is an automatic liquid level regulating gauge, and the one shown here is that which is furnished by the 5-0 Re ulator Company of Fostoria, Ohio, and C grown attached to the end of the distillin tubes B operates to open and close the va ve G which valve is connected with C by a diaphragm {1", valve C being positioned in the supply line C. It will be understood that any suitable method may be em loyed' for regulating the level of the liqui in the distilling tubes B. As this regulator is of standard equipment and operates on well-known principles,

and the valve operated by a diaphragm is of standard make and well understood, 1 do not go into the description of same here. nor do I claim any part of the regulator itself as new.

13 is a fitting connecting adjacent heating tube B to the supply line C. B is the fitting on the end of heating tubes 1P throu h which the oil in same is discharged into ine I). The line I) is connected to the bottom of the fitting B", which is secured to the distilling tubes B The oil is dis charged out through the bottom of the fitting B by means of the line E and through cooling tank E and then to any suitable storage, not shown, and between said storage and cooling tank E is positioned, in line E a throttle valve 111 to control the rate of flow of the residuum throu h the line E and a similar valve, marked is ositioned in the line E for obtaining samp of the residuum flowin through the line E F is a centri ugal pump. F is a motor for operating same. F is the suction line to the pump from the heating tubes B which comes out of the bottom of the fitting marked B". F is the discharge line which enters the side of the fitting marked B on the end of the heating tubes marked 15. F is a carbon trap on the end of the distilling coils attac led to the bottom of the fitting marked B.

G, G, G and G are upwardly inclined vapor lines leading oil of the distilling tubes B Lines (l and (i connect with a manifold G, which manifold connects by pipe G to fitting B attached to the distilling tubes B Lines G and G connect to a manifold G, which manifold connects, by means of pipe G to the top of fitting B on the ,end of the distilling, tubes 13*. These vapor lines G, G", G: and G are connected at their upper ends to a common header G, and have positioned on them throttle valves G G, .i and G. Said manifold (1 is connected to a top manifold G by means of bent pipes G to G and to the center of the top manifold U is connected pipe G which connects, in turn, to the coil G contained in the water tank G. From the coils G" the condenser extends through pipe G into the receiving tank H. From the pipe G is a branch pipe G having a pressure indicating gauge G, and out of the pipe G extends pipe G on the end of which is a valve G. This valve and gauge may be situated in the tail house and afford means for there regulating the pressure.

On the tank H are glthH liquid gauges H and H pressure reliel' valve H, draw valves H, H and H, and pressure gauge H H is for use in case water is to be drawn oil' before draining the distillate out through the valve H. H is a valve for use in an emergency, for example: when one of the other valves is removed for repair or renewal, and which valve is superficial for showing the workings of the apparatus.

J, J and J are supports for the receiving tank H. K is a support for the pipes shown.

L is a standard indicating pyrometer and. is connected with different thermosticks, which thermosticks are positioned in the furnace in which the tubes 13 and B are positioned. L is a standard temperature recording instrument and is connected to a thermostick by a cable, and which thcrmostick is positioned inside the manifold ti. L is a standard temperature recording instrument connected, by means of a cable, to thermosticks, which latter are positioned, one in the heating coils, to give the temperature of the oil contained therein and one positioned in the large distilling coils, to give the temperature of the oil contained therein. L is a standard indicating liquid gauge which is connected by tubing to the receiving tank H and shows the depth of the liquid contained in the receiving tank H. L is an electric switchboard of standard make, which board contains the standard knife switch for breaking or completing the circuit in operating the charging pump C; also a knife switch for breaking or completing the electric circuit for'controlling the motor C which operates the circulating pump (7; also a knife switch for breaking or completing the electric circuit for controlling the electric circulating pump F also a knife switch of standard make for breaking or completing the electric current for supplying the electric lights in the plant, all of which are enclosed in the house built beneath the water cooling tank C.

M is the gas main for suppl 'ing the furnace in which the tubes B and B are contained, and on this line is positioned throttle valve M N N N and N* are supports for the extensions 0 and 0 which extensions are simply housing over the ends of the heating tubes B and the distilling tubes B which housing is to revent more or less cooling effect that won d be caused by leaving them open to the atmosphere, and also to prevent subjecting the ends to varying temperatures.

Describing now the operation of the process, the material to be treated is drawn from any suitable source of supply through the line (7, by and through centrifugal pump C through line C into the heating tubes B then through line D to distilling tubes B and when these latter heating tubes have been filled to desired level, pump C is shut down and valve C on line C and valve C on line C are closed, and normally remain- Heat 1s ap started in operation and obtains its sup ly of raw material through line C and discharges through line C into line C, valve C being opened; and should the level of the liquid in the distilling tubes B be of the proper height, then the li uid level re ulator C will, by means of diaphragm close the valve C on the suppl line C, and the back pressure thus create on the line C will force open the pressure relief valve C" and by-pass the oil from the discharge side of the pump C back into the suction line C, and this. operation will continue until the level in the distilling tubes B drops to a suflicient point to permit the valve 0 to be automatically opened, thus admitting more raw material into the heating tubes B and B The pump 15" is put and maintained in operation, and the oil inthe heating tubes B made to circulate by drawing the oil through suction F and discharge back into the tubes through discharge F.

The residuum formed in the distilling tubes B can be drawn ofi either intermittently orcontinuously through line E through cooling coil contained in tank E and from there to any suitable storage. The quantity that is drawn off is regulated by means of valve E positioned in line B, and samples of said residuum may be obtained at any time through valve E in line B.

The vapors generated pass up through lines G, G G and G and into manifold G". and from there out through pipes G15 to G and into manifold G. All the vapors that are condensed up to this point are drained back into the distilling tubes 13*, while the remaining vapors pass through line I, through cooling coils G immersed in water in tank G and from there pass through line G into receiving tank H, from which they may be drawn off intermittently or continuously through valves H and H.

It will be seen that this method provides a process for automatically and continuously treating petroleum for the production of lower boiling oint products, and by means of the circulation of the liquid into heating tubes B permits of the furnace in which the tubes are positioned being maintained at a considerably higher heat Without injurious effect to the oil, and prevents any substantial deposit of carbon on the tubes.

The method while disclosed as being operated with a 1i uid level regulator, ma be as easily operate and in some cases pre erably,

by disconnecting the liquid level regulator and introducing fresh oil from time to time as the operator desires. In certain cases where a certain liquid level is maintain in the vaporizing chamber, the conditions of cracking cannot be maintained properly and it is necessary at times to either raise the liqluid level or allow it to lower to a point w ere more desirable and advantageous conditions of cracking are obtained. Also, the local circulation which is maintained in the heating zone through the pump F during the operation of the process, may be functioned during the initial stages to raise the oil to a cracking temperature before passing it to the distilling zone, that is, by circulating the oil only through the heating zone during the initial heating, it is ossible to raise the oil quicker to the desire temperature than where a greater quantity of oil is to be heated and the same must pass continuously through the entire system.

The entire system is preferably subjected to a vapor pressure of from 50 to 500 lbs., although the pressure will vary with the conditions. The temperature of the oil will preferably vary from 500 to 1000 Fahr., although I do not limit myself to these fig: ures. The pump is preferably operated so as to cause a relatively rapid circulation of the oil in the heating tubes.

I claim as my invention:

1. A process for cracking hydrocarbon oil, which consists in supplying oil under pressure to a heating zone, in passing heated oil trom the heating zone to a distilling zone, in' taking ofl? vapors from the distilling zone, in controlling the quantity of oil supplied to the heating zone by the liquid level of the oil maintained in the distilling zone and in continuously maintaining a local cyclic circulation of the oil undergoing treatment in the heating zone.

2. A continuous process for cracking oil consisting in pumping a stream of oil to a heating coil, where it. is locally circulated and raised to a cracking temperature, in delivering the highly heated oil to a distilling zone, in automatically maintaining a uniform quantity of oil in the distilling zone by returning a portion of the oil being pumped to the heating zone to the inlet of the pump employed in the process and in maintaining a super-atmospheric vapor pressure on the oil undergoing conversion.

oARBon P. DUBBS. 

